Lifting grapple with scissors tongs for handling concrete drainage rings



Jan. 10, 1967 A. c. cARLsoN 3,297,353

LIFTING GRAPPLE WITH SCISSORS TONGS FOR HANDLING CONCRETE DRAINAGE RINGS Filed Nov. 23, 1964 3 Sheets-Sheet 1 Jan. 10,1967 A. c. CARLSON LIFTING GRAPPLE WITH SCISSORS TONGS FOR HANDLING CONCRETE DRAINAGE RINGS 3 Sheets-Sheet 5 Filed Nov. 23. 1964 M M mm m M i E/jam W mwlwz 4 mjc w 25 a? w i r Y W B 9 m F llll United States Patent Ofilice Patented Jan. 10, 1967 3,297,353 LIFTING GRAPPLE WITH SCISSORS TONGS FOR HANDLING CONCRETE DRAINAGE RINGS Andrew Clifford Carlson, deceased, late of Suffolk County, N .Y., by Erna L. Carlson, executrix, 9 Bluff Point Road,

Suffolk County, Long Island, N.Y. 11978 Filed Nov. 23, 1964, Ser. No. 413,370

4 Claims. (Cl. 294-81) This application is related to copending application Serial No. 413,369, filed Nov. 23, 1964, entitled Lifting Grapple With Outside Gripper for Handling Concrete Drainage Rings.

This invention pertains to lifting grapples with scissors tongs for handling cylindrical objects, and more particularly to lifting grapples for lifting cured and uncured concrete drainage rings.

In the manufacture of precast concrete products, such as cylindrical drainage rings, after the concrete product has initially set, the mold is removed, and the uncured. or green concrete ring is then moved to. a storage area or loaded onto a truck for shipment. Conventional lifting hooks or grapples used heretofore have been unsatisfactory because they engage and support the wall of the drainage ring only at a few locations, and since the concrete wall, usually about 4 inches thick, is still green, it does not have sufiicient strength. to support the weight of the suspended drainage ring, and consequently the drainage ring very frequently cracks, crumbles, or is otherwise damaged.

It is therefore an object of this invention to overcome the above-mentioned difiiculties.

It is another object of the invention to provide a lifting and handling mechanism which will engage, at a multiplicity of peripheral locations, the walls of an open-top cylindrical object, with a minimum of stress or pressure being applied to the walls of the latter by the mechanism.

Still another object of the. invention is to provide a lifting and handling mechanism for cylindrical objects which is easy to attach and detach from the walls of the object being lifted, and which can be engaged and released there from by remote control.

A still further object of the invention is to provide attachments for a crane and for a forklift truck which attachments comprise a lifting and handling mechanism for lifting cylindrical objects, and which can be controlled by the operator of the crane or lift-truck to engage and disengage the load being lifted without additional personnel.

To these ends, and according to one feature of the invention, a frame is provided with a plurality of radially extending support arms, and scissors tongs are mounted at the outer ends of each of the arms. The scissors tongs are oriented so that their pairs of jaws open downwardly and are arranged in a circle whose diameter is that of the drainage ring to be lifted. Spring means keep the jaws of the scissors tongs normally in open position, and a pull cable attached to the upper end of each of the scissors tongs extends to a remote location for simultaneously actuating all the scissors tongs into closed position. A combination stand and centering guide member adjacent to each scissors tongs serves the purpose of supporting the entire mechanism on the ground when it is not in ring-supporting use, and this same member also serves to guide the wall of the concrete ring into the open jaws or clamping shoes of each scissors tongs as the mechanism is lowered over the concrete ring.

According to a modification of the invention, instead of a pull cable, the mechanism is remotely controlled into engaging and releasing position of the scissors tongs by means of a hydraulic or pneumatic cylinder.

" According to a further modification of the invention, the frame is'constructed with a movable portion and a fixed portion, each of said portions having a separate lifting hook at the top and approximate center of the mechanism. 1 The first lifting hook, i.e. the one attached to the fixed frame portion, serves to lower the entire grapple mechanism, suspended by this hook from a crane or lift-truck, and with jaws held open by springs, over the wall of the cylindrical ring to be lifted. The crane or lift-truck then shifts to engage the second hook. This second lifting hook, attached to the movable portion, serves to close the jaws of the scissors tongs so as to engage the load. The crane or lift-truck then lifts the load by raising the grapple mechanism by means of the second hook, and carries it to its distination. After the load is set. down, the spring biased jaws of the tongs open automatically, and the crane or lift-truck boom then shifts to the first hook to lift the grapple device and move it away.

The foregoing and other objects, advantages and features of my invention, these features being set forth with particularity in the claims annexed hereto, will be apparent from the following description in conjunction with the embodiments of a lifting grapple with scissors tongs according to the invention, illustrated by way of examples in the accompanying drawings, in which:

FIG. 1 is an elevation view, partially cut away, with the clamping jaws of the scissors tongs open before they engage the load to be lifted;

FIG. 2 is a plan view along line 2-2 of FIG. 1; FIG. 3 is a sectional view taken along line 33 of FIG.

FIG. 4 is a partial end view taken along line 44 of FIG. 1;

FIG. 5 is a partial view of the device of FIG. 1 with the scissors tongs in clamping position;

FIG. 6 is an elevation view of a modification of the device of FIG. 1;

FIG. 6A is a schematic plan view of the device of FIG. 6;

FIG. 7 is an elevation view of a further modification of the device of FIG. lshownin position with the jaws of the scissors tongs in open position;

FIG. 8 is a fragmentary cross section taken along line 88 of FIG. 7; and

FIG. 9 is a fragmentary view of the mechanism of FIG. 7 but with the scissors tongs shown in closed position and with the releasing hook being engaged by the lifting arm of a crane or lift truck.

The same or funtionally similar parts are designated by the same reference characters throughout the several views.

The cylindrical object 10 or 12 to be handled is shown in FIGS. 1 and 6, and in the examples herein disclosed it consists of a cast concrete septic tank or drainage ring of approximately six, eight, or ten feet in diameter. The walls of the cylindrical object may be solid as shown at 10 in FIG. 1, or may have spacedslotted perforations 14 for drainage.

The lifting mechanism designated generally in FIGS. 1 and 2 by the numeral 20 comprises four main portions: a star-shaped or polygonal frame, scissors tongs arranged at the outer corners of the frame, a centering guide which also servesas a pedestal, andcontrol means for the tongs. The frame itself comprises a plurality of upper horizontal radial arms 22 joined to a common vertical support column 24, a plurality of horizontal lower radial arms 28 also joined to the column 24, outer peripheral bracing members 26 and diagonal bracing members 30. The radial arms 22, 28 and vertical column 24 are preferably made of pipe or rod for lightness and strength, and the other members of angle iron.

At the outer ends of the radial arms 22, 28 are mounted scissors tongs generally designated by the numeral 32. These tongs are arranged at the outer corners of the frame. From two to eight pairs of peripherally arranged scissors tongs may be provided, with a frame built accordingly, to suit the diameter of the cylindrical objects to be lifted. Smaller diameter objects are lifted at fewer points spaced around their peripheries, and consequently fewer pairs of scissors tongs will be required. In the embodiments illustrated herein for the sake of examples only, three-point lifters are illustrated, with three corresponding sets of scissors tongs. However, it should be understood that any plurality of tongs may be similarly employed.

The scissors tongs 32 are each similar in construction and comprise a pair ofcrossed curved scissors levers 34, 34a, both pivoted at 36 to a supporting bracket 38 mounted at the outer end of each lower radial arm 28. At the lower end of each of the scissors levers 34, 34a is mounted one of a pair of shoes or jaws 40, to whose front faces are fastened a padded layer 42 of friction material, such as rubber. the lever arms 34, 34a by means of pin and slot connections to permit adjusting pivotal movement of the shoe as the sicssors tongs closes, so that the shoe 40 pivots about its pivot point 44 until the face of layer 42 is parallel to the vertical wall of the ring or 10. Each shoe 40 is provided with an inner block 43 which limits the swinging movement of the shoe 40 about its pivot 44, as shown in cutaway view at the left of FIG. 1. A pair of closing links 46, 46 are pivotally connected by means of pin and slot connections 48, 48 to the respective scissors arms 34, 34a, and the linkages 46 are pivotally joined to each other by means of a pin connection at 50. A biasing spring 52, connected between the pin 50 and the pivot 36, urges the pivot points 50 and 36 closer together and thus normally urges the jaws into spreadapart condition. For closing the jaws, each of the scis sors tongs 32 is provided with a closing line 54 connected by means of an eyelet to the pivot pin 50 and running over a pulley 56 rotatably mounted at the ends of the upper radial arms 22 of the frame. The closing lines 54 from each of the scissors tongs 32 are joined to a common ring 58 from which a single closing line 60 extends upwardly to where it can be controlled by the crane operator (not shown). In addition to the closing line 60, a lifting eye 62 is provided at the top of the central vertical support column 24 for being engaged by the lifting hook (not shown) or by a lifting line 64, which serves to suspend the weight of the entire mechanism and its load 10 from a crane or boom (not shown).

The supporting frame also includes vertical members 27 connecting the upper and lower radial arms 26, 28, and forming supports for the pulleys 56. As best shown in FIG. 4, the members 27 form openings through which levers 34 and 34a swing in mutual overlapping relationship.

Four linkage levers 46 are provided for each pair of scissors arms 34, 34a. The scissors arm 34a is sandwiched between a pair of arms 34 and also between a pair of linkages 46. As best shown in FIGS. 3 and 4, the structure of the scissors tongs is as follows, to prevent lateral bending. The outer lever member 34 comprises two plate levers, and the inner lever member 34a comprises a single plate lever which is sandwiched in between the outer two plates of member 34 at the pivot 36, and rotates in a plane between the planes of movement of the outer levers 34 of the same tongs.

The shoes are mounted onto A combination guide and supporting stand 70 is provided at the base of the device, at a plurality of locations. The device 70 has a foot portion 72 on which the entire grapple mechanism 20 can rest on the ground, and also a guiding face 74 which is aligned with the wall-engaging faces 42 of the jaws 40 when the scissors tongs 32 are in fully opened position. The device 70 also includes braces 76 and 78 for supporting it from respective members 26 and 28 of the grapple frame. The guiding face 74 of device 70 serves to center the grappling device 20 over the ring 10 by sliding across the upper corner of the ring 10 until the ring wall is between the jaws 40 and at the position 10' with respect to these jaws, as shown in FIG. 1.

A hook 80 is attached to the bottom of vertical post 24 for convenience in lifting or handling auxiliary loads without the necessity of removing the grapple 20 or its rings 62 and lines 60, 64 from the overhead crane or boom.

-In FIG. 5 the tongs 32 are shown in closed position with the jaws 40 gripping a slotted type concrete drainage ring 12 by means of their opposed surfaces 42. The control line 60 has been pulled upwardly by the operator in opposition to the force of spring 52 in order to close the jaws 40. The lifting line 64 is then raised by the crane to lift the entire grapple 20 with the load 12 clamped and suspended therefrom.

FIG. 6A shows the arrangement of the jaws 40 of the scissors tongs 32 located at the outer extremities of the radial arms 28. Each of the illustrated embodiments has three sets of jaws 40 located according to this arrangement.

The embodiment illustrated in FIG. 6 is similar to that shown in FIGS. 1-5, except that pneumatic closing means is provided in place of the manual closing lines 54, 60 of FIGS. 1-5 to close the jaws 40 of the tongs 32. The frame in this embodiment which supports the pluralllY'Of scissors tongs 32 has respective frame portions which move relative to each other so as to cause closing and opening of the jaws 40:0f the tongs 32 from the solid-line position to the dotted line position shown in FIG. 6. The cylinder 90, which may be fluid-operated by pneumatic or hydraulic means by a valve-controlled medium entering the cylinder through a pipe 92, is provided with a piston 94 reciprocable in cylinder 90 and connected to a piston rod 96. Rod 96 is linked to transverse members 126 of the frame so as to simultaneously lower the pivot points 36 of each of the scissors tongs when fluid is admitted through pipe 92.

In this embodiment the pivot pins 36-are transversely mounted in vertical rods 152 telescopically slidable within a tube 154, to which the upper links 46 of each of the scissors tongs 32 are pivoted at 150. The cylinder 90 is pivoted at its upper end by a bracket to the upper portion of the frame at 95 and its rod 96 is pivoted to the frame member 126 at 93, so that when the rod 96 moves downwardly in the direction of the arrow A, and the piston is moved from the solid line position to dotted line position 94', the pivot point 93 moves downwardly to position '93, the frame portion 126 moves to dotted line position 126, and the tong jaws 40 move to dotted line position 40'. A hook-eye 162 is provided in the upper fixed portion of the frame for engagement by a crane hook (not shown) which lifts the entire grapple mechanism together with its load 10. The upper portion of the frame comprises a center post 124 and diagonal braces 125 fixedly connected to the telescopic tubes 154 and movable relative to the pivot pins 36 as the rods 152 slide in the tubes 154. As in the embodiment of FIGS. 1-5, a combination pedestal and centering guide 70 is provided for resting the grapple device on the ground when not in use, and for also guiding the wall of the ring 10 into position between the respective jaws 40.

In the embodiment of FIGS. 7-9, scissors tongs are provided similar to those above-described with respect to FIGS. 1-5, and having telescopic rods and tubes 152, 154, respectively. FIG. 7 shows the grapple device with tongs 40 shown in open position in solid lines, the dotted lines illustrating the device in closed position. FIG. 9 illustrates the same device with the jaws 40 of the tongs 32 in solid line position and the jaws open in dotted line position.

The mechanism for opening and closing the jaws 40 in the embodiment of FIGS. 79 comprises a pair of hooks 262, 294 which are movable in a vertical direction relative to each other. The hook 294 is attached to a lower portion of the frame 126 connected to the pivot 36 of each scissors tongs, in much the same manner as the movable piston 94 of FIG. 6 is connected, so that vertical sliding movement of hook 294, relative to hook 262 and the frame portion attached to the latter, causes the pivot 36 of each scissors tongs 32 to be urged upwardly in relation to the pivot point 150. On the other hand, the other hook 262 is fixedly connected to the upper portion of the frame which includes radial arms 222 and cross bracing arms 226, at whose outer extremities the respective scissors tongs 32 are fastened by means of telescopic tubes 154 and .rods 152 slidable therein, as abovedescribed in relation to FIG. 6.

The hook 294 is provided with a slot 297 through which protrudes a pair of pins 295 to permit slidable movement of hooks 294 and 262 relative to each other guided by the pair of pins 295 fixedly attached to the vertical portion of hook 262 and projecting through and guided within the above-mentioned slot 297 of hook 294.

Operation of the device of FIGS. 79 is as follows. A crane or lift-truck, having an attachment 263 connected to its boom, engages the hook 294 of the grapple device while the latter is resting on the ground on its pedestals 70. The attachment 263 raises the hook 294 to position 294. The portion of the hook 294 which forms slot 297 slides upwardly relative to pins 295, pulling upwardly with it the connecting member 296. Frame member 126 moves to the dotted line position 126, pulling the pivot pin 36 up to position 36 as the rod 152 travels further into the tube 154. This movement forces the jaws 40 of the scissors tongs apart, in opposition to the normal urging downwardly of the point 150 and tube 154 by the weight of the upper portion of the frame attached to hook 262 (see FIG. 9). The entire grappling device is then lowered by the crane to a position over the ring 10 to be lifted, and is guided by means of pedestal guides 70 until the walls of the ring 10 are centered relative to the grapple mechanism and the walls are located between the jaws 40 of each of the scissors tongs.

To close the jaws and lift the load, the same attachment 263 attached to the crane or fork-lift truck boom then engages the other hook 262 to lift the latter to position 262' (FIG. 7) in the direction of arrow B. This raises the upper portion of the frame relative to its lower portion, hook 262 moves upwardly relative to hook 294 to the position 262', cross arm 226 moves to position 226, and pivot point 150 moves to position 153 to lift the respective tubes upwardly so as to partially withdraw the tubes 154 from their rods 152. This movement increases the vertical distance between pivot points 150 and 36, thus causing the jaws 40 to move laterally closer together into the dotted line position of FIG. 7 and thus to grip the walls of the drainage ring 10. Further upward movement of the attachment 263 in the direction of arrow B then lifts the entire load, and the crane or fork truck can move it to any desired location. The load is then set down and the jaws 40 are released. This releasing action takes place due to gravity when the bottom portion of rods 152 rest on the top edge of the drainage ring 10. The weight of the upper portion of the frame. pressing down on tubes 150, urges the pivot point 150 downwardly toward pivot point 36, so as to move the rod 152 further into the tube 154. The crane or lifttruck then raises the apparatus by means of attachment 263 engaging hook 294 as in FIG. 9, raising the latter to 6 position 294' so as to spread the jaws 45) into the dottedline position of FIG. 9. The attachment 263 is then lifted further in the direction of arrow D and the loadfree grapple is then raised away from the load in its destined location, and then moved away.

It will be obvious to those skilled in the art, upon a study of this disclosure, that this invention permits of various modifications and alterations with respect to the individual components and arrangements disclosed, and hence can be embodied in lifting devices other than as particularly illustrated and described herein, without departing from the essential features of the invention and within the spirit and scope of the claims annexed hereto.

I claim:

1. A lifting device for handling cylindrical objects, comprising a frame, a plurality of scissors tongs spacedly mounted around the periphery of said frame, each of said tongs having horizontally opposed jaws provided with load-engaging surfaces arranged to define a loadreceiving opening downwardly, means for urging said jaws into normally open position, control means for simultaneously operating said jaws into closed position, and guide means fixed to said frame for centering the device over the object to be lifted, said guide means com prising a foot portion for resting the lifting device on the ground and a guiding surface portion aligned with the load-engaging surface of one of said jaws when said jaws are in said open position.

2. A lifting device for handling cylindrical objects, comprising a frame having upper and lower portions movable relative to each other, a plurality of scissors tongs spacedly around the periphery of said frame, each of said tongs having a pair of mutually swingable levers, said levers being provided at their lower ends with horizontally opposed jaws arranged to define a load-receiving opening downwardly, means for urging said jaws into normally open position, and control means for simultaneously closing said jaws, said control means comprising a cylinder connected to one of said frame portions, said cylinder having a piston reciprocable therein, means for introducing a fluid into said cylinder for exerting pressure against said piston, a piston rod connected at one end to said pistion and at another end thereof to another of said frame portions, said levers of said tongs being pivotally attached to said other frame portion for movement therewith, each of said levers having a link pivotally attached to its upper end, the other ends of the links of each tongs being pivotally attached at a common point on said one frame portion, whereby when fluid is introduced into said cylinder said other portion of said frame is urged downwardly relative to said one frame portion so as to bring said closing shoes of a respective tongs into closer proximity to each other and to grip a load therebetween.

3. A lifting device for handling cylindrical objects, comprising a frame having upper and lower portions movable relative to each other, a plurality of scissors tongs spacedly mounted around the pheriphrey of said frame, each of said tongs having a pair of mutually swingable levers pivotally linked to said lower frame portion, said levers being provided at their lower ends with horizontally opposed jaws arranged to define a load receiving opening downwardly, means for urging said jaws into normally open position, and control means for simultaneously closing said jaws, each of said levers having a link pivotally attached to its upper end, the other ends of the links of each tongs being pivotally attached at a common point on the upper frame, said tongs including telescopic mounting means with tube means and rod means arranged for slidable telescopic engagement with each other, said tube means being connected to one of said frame portions and said rod means being connected to another of said frame portions.

4. Device according to claim 3, said control means comprising a pair of hooks approximately centrally positioned relative to said frame, a first of said hooks being fixedly attached to said upper frame portion, a second of said hooks being fixedly attached to said lower frame portion, said levers having a mutual pivot axis at their connection to said lower frame portion, said tube means being connected to said upper frame portion and said rod means being connected to said lower frame portion, so that vertical movement of said second hook upwardly relative to said upper frame portion forces said rod means telescopically into said tube means to raise said pivot axis of said levers and to thereby open said jaws.

References Cited by the Examiner UNITED STATES PATENTS 1,569,767 1/1926 Menamin 294-8l 2,815,878 12/1957 Vance 294-67 X 3,008,753 11/1961 TaZiOIi 294-81 X FOREIGN PATENTS 117,634 6/1958 Russia.

10 GERALD M. FORLENZA, Primary Examiner.

G. F. ABRAHAM, Assistant Examiner. 

3. A LIFTING DEVICE FOR HANDLING CYLINDRICAL OBJECTS, COMPRISING A FRAME HAVING UPPER AND LOWER PORTIONS MOVABLE RELATIVE TO EACH OTHER, A PLURALITY OF SCISSORS TONGS SPACEDLY MOUNTED AROUND THE PHERIPHERY OF SAID FRAME, EACH OF SAID TONGS HAVING A PAIR OF MUTUALLY SWINGABLE LEVERS PIVOTALLY LINKED TO SAID LOWER FRAME PORTION, SAID LEVERS BEING PROVIDED AT THEIR LOWER ENDS WITH HORIZONTALLY OPPOSED JAWS ARRANGED TO DEFINE A LOADRECEIVING OPENING DOWNWARDLY, MEANS FOR URGING SAID JAWS INTO NORMALLY OPEN POSITION, AND CONTROL MEANS FOR SIMULTANEOUSLY CLOSING SAID JAWS, EACH OF SAID LEVERS HAVING A LINK PIVOTALLY ATTACHED TO ITS UPPER END, THE OTHER ENDS OF THE LINKS OF EACH TONGS BEING PIVOTALLY ATTACHED AT A COMMON POINT ON THE UPPER FRAME, SAID TONGS INCLUDING TELESCOPIC MOUNTING MEANS WITH TUBE 